Engineers from Bosch work under innovative fast-charging batteries

Not so long time ago we were talking about Bosch and its lofty goals – the company was promising to develop a fast-charging battery with not only unbelievable energy density (300 watt-hours per kilogram) but also low weight and affordable price.

At the inauguration of the Renningen research campus, Bosch announced goals for its battery developments.

Here’s what the company was promising:

1) Increased energy density

Dr. Thorsten Ochs, head of battery technology R&D at the new Bosch research campus in Renningen, explained to us what is necessary for progress in battery technology: “to achieve widespread acceptance of electromobility, mid-sized vehicles need to have 50 kilowatt-hours of usable energy.”

2) Weight reduction

With conventional lead batteries, this would mean increasing the weight of the battery to 1.9 metric tons, even without wiring and the holder. That is the same weight as a modern-day mid-sized sedan, including occupants and luggage. At a weight of 19 kilograms, a conventional lead battery stores a comparatively low 0.5 kilowatt hours.

Today’s lithium-ion batteries are superior in this respect. They store more than three times the amount of energy per kilogram. At a weight of 230 kilograms, the battery of a modern-day electric car provides approximately 18 to 30-kilowatt hours. But to achieve the desired 50-kilowatt hours, a battery weighing 380 to 600 kilograms would be necessary.

3) Fast charging

“Our new batteries should be capable of being loaded to 75 percent in less than 15 minutes”- Ochs said.

At first sight, seems like impossible things to do, isn’t it?

Luckily, thanks to masterminds from Bosch, it has become possible.

Brief explanation

The more lithium ions you have in a battery, the more electrons--and thus the more energy --you can store in the same space.

Sounds quite simple, isn’t it?

Just add lithium ions and that’s all.

Nonetheless, everything is not as simple as that.

Researchers needed to improve cells at the atomic and molecular level in order to make this possible and, believe you or not, it was hard as hell.

They had to come up with their own mechanism --the reduction of the proportion of graphite in the anode—to make this possible.

Using lithium instead of graphite made it feasible to store up to three times as much energy in the same space.

*Anode is the positively charged part of the battery.

Cooperation with other companies

To make progress in this area, his team in Renningen is working closely with Bosch experts in Shanghai and Palo Alto. And as a further measure to advance lithium-ion battery research, Bosch has established the Lithium Energy and Power GmbH & Co. KG joint venture with GS Yuasa and the Mitsubishi Corporation.

Plans for the future

Ochs and his colleagues have already developed many approaches for removing the graphite and replacing it with other materials.

The team of researchers aims to experiment with that.

Additionally, Ochs and his team want to replace liquid electrolyte with something less dangerous – as of now, liquid electrolytes can only to be found in conventional lithium-ion batteries, where, in certain circumstances, it can pose a safety risk.

Well, good luck with that one.

The cheaper and safer batteries, the more appealing EVs will be for the customers.

⁪

⁪

*Bosch expects 15% market share for electric cars around 2025 and because of that invests 400 million euros (460 million US dollars) annually in electromobility to be ready as a leading automotive supplier for the New Energy Vehicles.